Many micro-electromechanical systems (MEMS) require transparent substrates which allow light to pass through the substrate and to and through features of the device. Examples of such MEMS devices include BioMEMs, which include devices where biological material is manipulated to analyze and measure its activity, and Optical MEMs or micro-optoelectromechanical systems (MOEMS). MOEMs devices may be used for optical switching, scanners, displays, and various other optical applications.
There can be issues with the use of transparent substrates (e.g., wafers) during the device fabrication processes. Many fabrication tools can not locate or recognize a transparent substrate with the typical detection methods employed. For example, typical tools may use radiation that is reflected from the substrate to determine a substrate's presence and/or alignment. With transparent substrates, the radiation may not be sufficiently reflected.
Thus, what is needed is an improved design for a transparent substrate.